Drill feed



Nov. 29, 1966 J. r. DOYLE 3,287,996

DRILL FEED Filed Nov. 23, 1964 l IILOII mvsu'roa JAMES T DOYLE United States Patent 3,287,996 DRILL FEED James T. Doyle, 2220 E. 6th Ave., Vancouver, British Columbia, Canada Filed Nov. 23, 1964, Ser. No. 412,966 Claims. (Cl. 7733.5)

This invention relates to power drills and more particularly to the feed apparatus by means of which a drill may be advanced towards the work.

In the use of power drills, particularly where a relatively hard material is to be drilled, the use of a coolant to lower the temperature of the drill at the work face, is essential. Most drilling apparatus therefore is provided with means whereby a cooling fluid may be directed between the drill bit and the work. However, in such apparatus there is usually no correlation between the movement of the bit into the work and the ejection of the cooling fluid. The ejection of cooling fluid and the advancement of the drill bit into the work being independent of one another sometimes results in damage to the work and to the drill should the flow of cooling fluid, for one reason or another, stop.

The present invention provides a feed apparatus for drills in which the cooling fluid also serves as a means whereby the drill may be advanced into the work, the operation of the cooling fluid being such that the drill may not be advanced unless, at the same time, a cooling fluid is ejected to cool both the bit and the work.

The present invention also provides a drill feed apparatus in which the rate of flow of the cooling fluid is entirely dependent upon the rate of the advancement of the drill into the work so as to provide sutficient cooling fluid where high boring speeds and, consequently, high rate of advancement produces excessive heat between the parts.

The present invention comprises a supporting frame, means for slidably mounting a drill on said frame for reciprocal movement towards and away from the work, a hollow cylinder member, a piston member in said cylinder member dividing the latter into two chambers of variable size, each of said chambers being arranged to be filled with a fluid, means rigidly connecting one of the members to the frame, means connecting the other member to the drill for cooperative movement therewith, valve controlled distributor means for selectively and alternately connecting a selected one of either of the chambers with the drill bit, and means directionally controlled by said distributor means, operable when one of the chambers is connected to the bit, for supplying the other chamber with a fluid under pressure to thereby move the movable member and hence the drill.

In the drawings which illustrate the embodiments of the invention,

FIGURE 1 is a side elevation of one embodiment of the invention showing the drill mounted thereto,

FIGURE 2 is a front elevation of the invention of FIGURE 1,

FIGURE 3 is a sectional view taken on the line 33 of FIGURE 1,

FIGURE 4 is an enlarged view taken along line 44 of FIGURE 1,

FIGURE 5 is a sectional view taken on line 5-5 of FIGURE 4, and

FIGURE 6 is a side elevation illustrating another embodiment of the invention.

Referring to the drawings, FIGURES 1 to 5 thereof illustrate one embodiment 10 of the invention which comprises a heavy frame 11 having a horizontal base 12 at one edge 13 of which is welded a heavy vertical back 3,287,996 Patented Nov. 29, 1966 plate 14 having a longitudinally extending vertical slot 16 formed therein. At the upper end 17 of the back plate are fixed, as by welding, a pair of spaced parallel side plates 18, the latter extending outwardly over said base 12. Gussets,19 are provided between the back plate 14 and base 12 in order to strengthen the frame.

Mounted on the frame adjacent to but spaced outwardly from the slot 16 is an elongated vertical rod or shaft 20, the lower end 21 being fixed to the base 12 as by welding, and passes at its upper end 22 through a suitably sized hole in a horizontal bracket 23, the latter being secured as :by welding to the back plate 14. A set screw 24 is provided in the bracket 23 by means of which the rod or shaft 20 may be firmly and immovably positioned therein relative to said frame 11. Rigidly secured to the shaft 20 at or near its middle length, is a thin piston 26. This piston may be formed as an integral part of the shaft when machining the latter, or may be welded thereto, and is provided with a peripheral groove 27 adapted to receive a rubber O-ring 28. The rod or shaft 20 is also provided with a pair of longitudinally extending internal passages 29 and 30 extending from the upper end 22 of said rod, passage 29 having a port 32 adjacent to but above the piston 26 and passage 30 having a port 33 adjacent to but below said piston.

A thick walled elongated cylinder 36 is arranged over the shaft and piston 26 and has an inside diameter a little less than the diameter of the O-ring so that a tight but yet slidable seal is obtained. Each of the ends 37 and 38, respectively, of the cylinder is provided with annular cylinder heads 39 and 40, respectively, each being provided with internal annular grooves 42 adapted to receive rubber O-rings 43 by means of which each affects a tight yet slidable seal with the rod or shaft 20. The piston 26 thereby divides the cylinder into two variably sized chambers, an upper chamber 45 and a lower chamber 46.

Secured to the cylinder 36 is a horizontally extending bracket 48 having a dog or lug 49 extending outwardly of the walls of the cylinder and into the slot 16 of the back plate 14. The lug 49 is slidable in said slot and permits vertical movement of the cylinder but prevents rotation of the latter. The bracket 48 is formed at its side opposite the lug 49 with a pair of spaced arms 50.

In the use of the apparatus, it is proposed to employ an electrically powered drill which may be secured either as a permanent element of the apparatus or, if desired, may be temporarily aflixed thereto.

The numeral 51 designates a relatively standard type of drill having an enlarged motor or casing 52 and extending therefrom a drive shaft 53. The drill is arranged and located relative to the apparatus with the arms extending around and embracing the casing 52 so that the drive shaft 53 extends vertically downwardly in parallel alignment with the rod or shaft 20. The arms 50 may be either welded to said casing if it is desired to pennanently mount the drill. However, if it is desired to temporan'ly mount the drill, the arms may be formed so that they extend completely around the casing and tightened thereover by means of a wing nut or the like, not shown. The type of drill chosen shall be such that the drive shaft 53 thereof may be provided with a water swivel 54 and chuck 55 adapted to hold a hollow bit 56. This type of drive and the component parts thereof are of known manufacture and usage and need not be further described.

The passages 29 and 30 in the rod 20 are each connected through conduits and 61, respectively, to a valve-controlled distributor 63, the latter being secured firmly between side plates 18. The distributor 63 also has a connection by a flexible conduit 64 to the water swivel 54 and is also connected by a conduit 65 to an electrically driven pump 66, the latter being connected to a source of fluid, such as water, not shown.

The distributor 63 takes the form of a short, thick walled, hollow cylinder 67, having four passageways 68, 69, 70 and 71 extending through its wall and terminating in ports 73, 74, 75 and 76, respectively, spaced equidistantly apart and in the same radial plane, at the inner surface 78 of the cylinder walls. Conduits 60 and 61 are each connected to passageways 68 and 69, respectively, while conduits 64 and 65 are each connected to passageways 70 and 71, respectively. The distribution of coolant entering the distributor by the conduit 65 is controlled by a valve 80, the latter being cylindrical in shape adapted to make a tight, yet slidable contact with the inner surface 78 of the hollow cylinder. The valve extends outwardly at each of its ends 83 and 84, respectively, beyond the ends of the cylinder and is provided with an annular shoulder 85 adjacent its end 83, and with a nut 87 at its other end 84 by means of which it may be restrained from axial movement relative to cylinder 67. The valve 80 is also provided with a pair of transversely extending parallel slots formed diametrically opposite each other near its middle length and located in the same radial plane, when the valve is properly located, as the ports 73-76. The slots 87 and 88 are spaced apart, extending between them an oblong portion 90, the ends 92 and 93 of which still maintain a slidable, yet tight fit with the walls of the cylinder 67.

The end 83 of the valve is provided with a handle 95 by means of which the valve may be rotatably moved between its operative positions. One of these operative positions of the valve is shown in solid lines in FIGURE 5, in which the latter is located so that ports 74 and 76 are connected through slot 87, while ports 73 and 75 are connected through slot 88. With this setting of the valve, it will be seen that chamber 46 is therefore connected to the source of pressurized coolant, whereas chamber 45 is connected to the water swivel 54. It may be observed that the valve 80 may also be positioned so that its ends 92 and 93 may confront and close ports 76 and 75 to thereby shut off the flow of coolant to the distributor.

In the operation of the apparatus, the conduit system and chambers 45 and 46 are first filled with a coolant, and the drill 51 and pump 66 set in operation through the closure switch 97 which is connected to both the electric motor driving the pump and the drill through leads 98. The valve 80 is then positioned so as to connect chamber 45 with a source of pressurized coolant so as to move cylinder 36 and with it the drill upwardly along the rod 20. This action exhausts the pressurized coolant from chamber 46 through the distributor and into the water swivel 54. When the drill has been moved upwardly to provide sufficient room for the work to be placed thereunder, the position of the valve is then reversed to connect chamber 46 with the pressurized source coolant and to connect chamber 45 with the swivel, thereby moving the cylinder 36 and with it the drill towards the work and, at the same time, exhausting through the distributor, the coolant in chamber 46, said coolant flowing into the swivel and through the drill bit. The pressurized coolant acting on the cylinder 36 to continually feed the latter into the work and, at the same time, exhaust the coolant fluid in chamber 45 into the swivel and through the drill bit. As the drill advances, it will be seen that coolant is continually fed through the drill bit, the rate of advancement of the drill through the work governing the rate of flow of the coolant fluid from chamber 45. It will be seen, therefore, that the drill cannot be advanced into the work without the emission of coolant through the drill bit. This safety feature will always insure the continual flow of coolant while the drill is working. In some cases where the material to be drilled is extremely hard, a feature which naturally tends to retard the progress of the drill through the work, and therefore perhaps result in an insufiicient flow of coolant fluid. A valve may be employed having a thin passageway 100 extending between the slots 87 and 88. The provision of this passageway 100 which must be of a sufliciently small diameter so as not to reduce the operative pressures in the conduit 65, will always insure that when the drill is working, coolant will be supplied via slots 87 and 88 directly from conduit 65 into the water swivel 54 to supplement the coolant being exhausted from chamber 45.

FIGURE 6 illustrates another embodiment of the apparatus. Apparatus 110 includes the provision of a frame 111 constructed in the same manner as frame 11 of apparatus 10 having a back plate 113 and a base 114, said back plate also having a vertically extending slot 115 formed therein. Apparatus 110, however, differs from apparatus 10 in the provision of a cylinder 116,

similar in construction to cylinder 36, but ridigly secured by brackets 117 to the back plate 113. Apparatus 110 is also provided with a piston .carrying rod 118 extend ing through the cylinder 116 and secured at its ends 119 to spaced horizontal arms 120 of a carrying bracket 122. The arms 120 slidably extend through the slot 115 at their ends 123 and are secured in spaced apart relationship by means of a vertically extending frame member 124 at their other end, said frame member being provided with clamps or brackets 125 by means of which a drill 127 may be secured to said carrying bracket for cooperative reciprocal movement with the rod 118.

In apparatus 116, as the cylinder 116 is fixed, it may be connected directly from each end thereof by means of conduits 130 to a distributor, in the same manner as passageways 29 and 30 of the rod 20 are connected to the distributor 63. The operation of apparatus 110 is exactly the same as the operation of apparatus 10, the only difference lying in a reciprocating rod rather than a reciprocating cylinder.

What I claim as my invention is:

1. Feed apparatus for a drill having a tubular bit comprising a supporting frame, means for slidably mounting a drill on said frame for reciprocal movement towards and away from the work, a hollow cylinder member, a piston member in said cylinder member dividing the latter into two chambers of variable size, each of said chambers being arranged to be filled with a fluid, means rigidly connecting one of the members to the frame, means connecting the other member to the drill for cooperative movement therewith, valve controlled distribution means for selectively and alternately connecting a selected one of either of the chambers with the drill bit, and means directionally controlled :by said distribution means, operable when one of the chambers is connected to the bit, for supplying the other chamber with a fluid under pressure to thereby move the movable member and hence the drill.

2. Feed apparatus for a drill having a tubular bit comprising a supporting frame, means for slidably mounting a drill on said frame for reciprocal movement towards and away from the work, a hollow cylinder member, a piston in said cylinder member dividing the latter into two chambers of variable size, each of said chambers being arranged to be filled with a fluid, an elongated piston rod member connected to the piston and extending outwardly beyond the cylinder, said piston rod having a pair of fluid passageways extending longitudinally of the rod from an end thereof, and each terminating at opposite chambers, one of said members being rigidly connected to the frame .and the other to the drill for cooperative movement with the latter, valve controlled.

distributor means having a conduit connected to each of the passageways and to the bit for selectively and alternately connecting a selected one of either of the chambers with said bit, means directionally controlled by said distributor when one of the chambers is connected to the bit for supplying the other chamber with a fluid under pressure, to thereby move the movable member and hence the drill.

3. Feed apparatus for a drill having a tubular bit comprising a supporting frame, means for slidably mounting a drill on said frame for reciprocal movement towards and away from the work, a hollow cylinder connected to the drill for reciprocal movement therewith, a piston slidably mounted in the cylinder and rigidly connected to the frame, said piston dividing the cylinder into two variably sized chambers, valve controlled distributor means for selectively and alternately connecting a selected one of either of the chambers with the drill bit, and means directionally controlled by said distribution means, operable when one of the chambers is connected to the bit, for supplying the other chamber with a fluid under pressure to thereby move the movable member and hence the drill.

4. Feed apparatus for a drill having a tubular bit comprising a supporting frame, means for slidably mounting a drill on said frame for reciprocal movement towards and away from the work, a hollow cylinder connected to the drill for reciprocal movement therewith, said cylinder having annular sealing means at each end, an elongated rod extending through both annular sealing means and rigidly connected at each end to the frame, a piston fixedly mounted on the rod adjacent the latters middle length, said piston dividing the cylinder into two variably sized chambers, a pair of fluid passageways formed through the rod extending longitudinally thereof from one end and each terminating in ports in each chamber adjacent opposite sides of the piston, valve controlled distributor means having a conduit connected to each of the passageways and to the bit for selectively and alternately connecting a selected one of either of the chambers with said bit, means directionally controlled by said distributor when one of the chambers is connected to the bit for supplying the other chamber with a fluid under pressure to thereby move the movable member and hence the drill.

5. Feed apparatus for a drill having a tubular bit comprising a supporting frame, means for slidably mounting a drill on said frame for reciprocal movement towards and away from the work, -a hollow cylinder rigidly connected to the frame, said cylinder being closed at one end having annular sealing means at the other end, a piston mounted in the cylinder for reciprocal movement, said piston dividing the cylinder into two variably sized chambers, the latter arranged to be filled with a fluid, a piston rod connected at one end to the piston and extending at its other end through the annular sealing means, said piston rod operatively connected to the drill for mutual reciprocal movement with the latter, a valve controlled distributor having a conduit connected to each of the chambers, the bit and a source of fluid under pressure adapted to be alternately and selectively operated to selectively connect a selected one of either of the chambers with the drill bit and at the same time connect the chamber not connected with the bit, to the source of fluid under pressure, to thereby move the piston and hence the drill.

References Cited by the Examiner UNITED STATES PATENTS 1,208,289 12/1916 Carrol 7733.5 1,317,711 10/1919 Landgraf 77-335 2,686,440 8/1954 Van Cutsem 77-55 FRANCIS S. HUSAR, Primary Examiner. 

1. A FEED APPARATUS FOR A DRILL HAVING A TUBULAR BIT COMPRISING A SUPPORTING FRAME, MEANS FOR SLIDABLY MOUNTING A DRILL ON SAID FRAME FOR RECIPROCAL MOVEMENT TOWARDS AND AWAY FROM THE WORK, A HOLLOW CYLINDER MEMBER, A PISTON MEMBER IN SAID CYLINDER MEMBMER DIVIDING THE LATTER INTO TWO CHAMBERS OF VARIABLE SIZE, EACH OF SAID CHAMBERS BEING ARRANGED TO BE FILLED WITH A FLUID, MEANS RIGIDLY CONNECTING ONE OF THE MEMBERS TO THE FRAME, MEANS CONNECTING THE OTHER MEMBER TO THE DRILL FOR COOPERATIVE MOVEMENT THEREWITH, VALVE CONTROLLED DISRTRIBUTION MEANS FOR SELECTIVELY AND ALTERNATELY CONNECTING A SELECTED ONE OF EITHER OF THE CHAMBERS WITH THE DRILL BIT, AND MEANS DIRECTIONALLY CONTROLLED BY SAID DISTRIBUTION MEANS, OPERABLE WHEN ONE OF THE CHAMBERS IS CONNECTED TO THE BIT FOR SUPPLYING THE OTHER CHAMBER WITH A FLUID UNDER PRES- 